<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>

<style>
    .box {
        display: flex;
    }

    .box input {
        display: block;
        width: 100px;
        height: 20px;
        border: 1px solid #000; /* 设置边框 */
        margin-right: -1px; /* 使边框重叠的部分消失 */
    }

</style>
<body>


<div class="box">
    <input type="text">
    <input type="submit">
</div>

</body>
</html>